Doorbell sound output device controllers, doorbell switches, and associated systems and methods

ABSTRACT

A doorbell switch includes a user input device configured to receive a user command to activate a doorbell sound output device, and activation circuitry configured to generate an activation signal in response to the user input device receiving the user command to activate the doorbell sound output device. A doorbell sound output device controller includes a switching device configured to control flow of electrical current between the doorbell sound output device controller and the doorbell sound output device, and control circuitry configured to control the switching device to enable flow of electrical current between the doorbell sound output device controller and the doorbell sound output device in response to receiving the activation signal from the doorbell switch.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/868,920, filed on Jan. 11, 2018, which claims benefit of priority toU.S. Provisional Patent Application Ser. No. 62/445,184, filed on Jan.11, 2017. Each of the above-mentioned applications is incorporatedherein by reference.

BACKGROUND

Doorbells are widely used in buildings, such as to enable visitors toannounce their presence. FIG. 1 schematically illustrates a prior-artdoorbell system 100 including a stepdown transformer 102, a doorbellswitch 104, and a mechanical doorbell sound output device 106. A primarywinding 108 of the transformer 102 is electrically coupled to analternating current (AC) electrical power source (not shown), and asecondary winding 110 of the transformer 102 is electrically coupled inseries with the doorbell switch 104 and the doorbell sound output device106.

The doorbell switch 104 is normally open, and electrical currenttherefore normally does not flow through the mechanical doorbell soundoutput device 106. When the doorbell switch 104 is pressed such that theswitch is closed, electrical current flows through and energizes themechanical doorbell sound output device 106. Typically, this actionproduces a “ding” sound. When the doorbell switch 104 is released suchthat the switch is opened, a plunger of the mechanical doorbell soundoutput device 106 strikes a lower pitched metal plate, producing a“dong” sound. The mechanical doorbell sound output device 106 isschematically depicted herein as a solenoid coil, and mechanical aspectsare not shown to promote illustrative clarity.

FIG. 2 schematically illustrates another prior-art doorbell system 200.The doorbell system 200 is similar to the doorbell system 100 of FIG. 1,except that the mechanical doorbell sound output device 106 is replacedwith an electronic doorbell sound output device 206, and a semiconductordiode 212 is electrically coupled in parallel with the doorbell switch104. The semiconductor diode 212 provides half-wave rectified directcurrent (DC) electrical power to the electronic doorbell sound outputdevice 206, thereby enabling the doorbell sound output device 206 to beready to receive a trigger signal. When the doorbell switch 104 isclosed, the electronic doorbell sound output device 206 is triggered bythe presence of an AC electrical current waveform flowing through thedoorbell sound output device. When the doorbell switch 104 is released,DC electrical power is again provided to the electronic doorbell soundoutput device 206, thereby electrically powering the electronic doorbellsound output device 206 and enabling the doorbell sound output device tocontinue to play a sound output device melody lasting a few to severalseconds, even if the trigger signal is shorter than one second. Manyelectronic doorbell sound output devices on the market today operate inthis manner, requiring a diode (e.g., the diode 212) connected acrossthe doorbell switch.

SUMMARY

One aspect of the present embodiments includes the realization thatclosure of a switching device in a conventional doorbell switchelectrically bypasses a power supply of the doorbell switch.Consequently, if the doorbell switch is to operate continuously, abattery or other energy storage device must be provided to power thedoorbell switch while the switching device is closed. The presentembodiments solve this problem by generating an activation signal in adoorbell switch without interfering with power supply circuitryoperation in the doorbell switch, and enabling flow of electricalcurrent between a doorbell sound output device controller and a doorbellsound output device in response to receiving the activation signal atthe doorbell sound output device controller. Doorbells includingfeatures of the present embodiments thus do not require a battery orother energy storage device to power the doorbell switch while theswitching device is closed, which not only simplifies the structure ofsuch doorbells, but also enables doorbells of the present embodiments toavoid drawbacks associated with batteries, such as their limitedlifespan and poor cold weather performance.

In a first aspect, a doorbell sound output device controller includes(a) a switching device configured to control flow of electrical currentbetween the doorbell sound output device controller and a doorbell soundoutput device and (b) control circuitry. The control circuitry isconfigured to control the switching device to enable flow of electricalcurrent between the doorbell sound output device controller and thedoorbell sound output device in response to receiving an activationsignal from a doorbell switch external to the doorbell sound outputdevice controller.

In some embodiments of the first aspect, the control circuitry includesa receiver configured to receive the activation signal from the doorbellswitch.

In some embodiments of the first aspect, the receiver is configured toreceive the activation signal via wiring electrically coupling thedoorbell switch to the doorbell sound output device controller.

In some embodiments of the first aspect, the activation signal isselected from the group consisting of a simple tone and a modulatedtone.

In some embodiments of the first aspect, the control circuitry includescurrent sense circuitry configured to receive the activation signal fromthe doorbell switch via a change in electrical current flowing betweenthe doorbell sound output device controller and the doorbell switch.

In some embodiments of the first aspect, the current sense circuitryincludes (a) an electrical conductor configured to be electricallycoupled to the doorbell switch, and (b) a Hall effect sensor configuredto sense a magnetic field generated by electrical current flowingthrough the electrical conductor.

In some embodiments of the first aspect, the control circuitry isfurther configured to detect the activation signal in response to achange in an amount of time that a magnitude of the electrical currentflowing between the doorbell sound output device controller and thedoorbell switch is zero.

In some embodiments of the first aspect, the control circuitry includesfiltering circuitry configured to filter the activation signal fromother signals received by the control circuitry.

In some embodiments of the first aspect, the control circuitry includes(a) a power supply configured to provide electric power to the controlcircuitry, and (b) driver circuitry configured to drive the switchingdevice.

In some embodiments of the first aspect, the switching device isconfigured to be electrically coupled in series with the doorbell soundoutput device.

In some embodiments of the first aspect, the switching device includes atriac.

In some embodiments of the first aspect, the doorbell sound outputdevice controller further includes a diode device electrically coupledin parallel with the switching device, such that the diode deviceprovides a path for direct current between the doorbell sound outputdevice controller and the doorbell sound output device.

In some embodiments of the first aspect, the switching device includesfirst and second metal oxide semiconductor field effect transistorselectrically coupled in series, and the diode device is a body diode ofthe first metal oxide semiconductor field effect transistor.

In some embodiments of the first aspect, the control circuitry isfurther configured to receive a configuration command to cause thesecond metal oxide semiconductor field effect transistor to continuouslyoperate in its conductive operating state, such that the body diode ofthe first metal oxide semiconductor field effect transistor provides apath for direct current between the doorbell sound output devicecontroller and the doorbell sound output device.

In some embodiments of the first aspect, the control circuitry isfurther configured to receive the configuration command from thedoorbell switch.

In some embodiments of the first aspect, the control circuitry isfurther configured to control a duration that the switching deviceoperates in its conductive state in response to receiving the activationsignal from the doorbell switch.

In some embodiments of the first aspect, the control circuitry isfurther configured to enable adjustment of the duration that theswitching device operates in its conductive state in response toreceiving the activation signal from the doorbell switch.

In a second aspect, a doorbell switch includes (a) a user input deviceconfigured to receive a user command to activate a doorbell sound outputdevice, and (b) a transmitter configured to generate an activationsignal on wiring electrically coupling the doorbell switch to a doorbellsound output device controller, in response to the user input devicereceiving the user command to activate the doorbell sound output device.

In some embodiments of the second aspect, the doorbell switch furtherincludes power supply circuitry configured to (a) receive inputelectrical power via the wiring electrically coupling the doorbellswitch to the doorbell sound output device controller and (b)electrically power the doorbell switch.

In some embodiments of the second aspect, the transmitter is furtherconfigured to generate the activation signal such that the activationsignal is selected from the group consisting of a simple tone and amodulated tone.

In some embodiments of the second aspect, the user input device includesa touch-activated switch.

In some embodiments of the second aspect, the doorbell switch furtherincludes a video camera configured to generate video image datarepresenting a scene proximate to the doorbell switch.

In some embodiments of the second aspect, the doorbell switch furtherincludes a microphone configured to generate sound data representingsound proximate to the doorbell switch.

In some embodiments of the second aspect, the doorbell switch furtherincludes a speaker configured to generate sound in response to a signalreceived by the doorbell switch from a device external to the doorbellswitch.

In a third aspect, a doorbell switch includes (a) a user input deviceconfigured to receive a user command to activate a doorbell sound outputdevice, and (b) perturbation circuitry configured to generate anactivation signal on wiring electrically coupling the doorbell switch toa doorbell sound output device controller by changing electrical currentflowing through the wiring, in response to the user input devicereceiving the user command to activate the doorbell sound output device.

In some embodiments of the third aspect, the doorbell switch furtherincludes power supply circuitry configured to (a) receive inputelectrical power via the wiring electrically coupling the doorbellswitch to the doorbell sound output device controller and (b)electrically power the doorbell switch.

In some embodiments of the third aspect, the perturbation circuitryincludes a perturbation switching device and an impedance deviceelectrically coupled in series across the wiring electrically couplingthe doorbell switch to the doorbell sound output device controller.

In some embodiments of the third aspect, the user input device includesa touch-activated switch.

In some embodiments of the third aspect, the doorbell switch furtherincludes a video camera configured to generate video image datarepresenting a scene proximate to the doorbell switch.

In some embodiments of the third aspect, the doorbell switch furtherincludes a microphone configured to generate sound data representingsound proximate to the doorbell switch.

In some embodiments of the third aspect, the doorbell switch furtherincludes a speaker configured to generate sound in response to a signalreceived by the doorbell switch from a device external to the doorbellswitch.

In a fourth aspect, a doorbell includes a doorbell switch and a doorbellsound output device controller. The doorbell switch includes (a) a userinput device configured to receive a user command to activate a doorbellsound output device, and (b) activation circuitry configured to generatean activation signal in response to the user input device receiving theuser command to activate the doorbell sound output device. The doorbellsound output device controller includes (a) a switching deviceconfigured to control flow of electrical current between the doorbellsound output device controller and the doorbell sound output device, and(b) control circuitry configured to control the switching device toenable flow of electrical current between the doorbell sound outputdevice controller and the doorbell sound output device in response toreceiving the activation signal from the doorbell switch.

In some embodiments of the fourth aspect, the doorbell switch furtherincludes power supply circuitry configured to (a) receive inputelectrical power via wiring electrically coupling the doorbell switch tothe doorbell sound output device controller and (b) electrically powerthe doorbell switch.

In some embodiments of the fourth aspect, the activation circuitryincludes a transmitter configured to generate the activation signal onthe wiring electrically coupling the doorbell switch to the doorbellsound output device controller.

In some embodiments of the fourth aspect, the transmitter is furtherconfigured to generate the activation signal such that the activationsignal is selected from the group consisting of a simple tone and amodulated tone.

In some embodiments of the fourth aspect, the activation circuitry isfurther configured to generate the activation signal by changingelectrical current flowing through the wiring electrically coupling thedoorbell switch to the doorbell sound output device controller.

In some embodiments of the fourth aspect, the activation circuitryincludes a perturbation switching device and an impedance deviceelectrically coupled in series across the wiring electrically couplingthe doorbell switch to the doorbell sound output device controller.

In some embodiments of the fourth aspect, the doorbell switch furtherincludes a video camera configured to generate video image datarepresenting a scene proximate to the doorbell.

In some embodiments of the fourth aspect, the control circuitry of thedoorbell sound output device controller includes a receiver configuredto receive the activation signal from the doorbell switch via the wiringelectrically coupling the doorbell switch to the doorbell sound outputdevice controller.

In some embodiments of the fourth aspect, the control circuitry of thedoorbell sound output device controller includes current sense circuitryconfigured to receive the activation signal from the doorbell switch viaa change in electrical current flowing between the doorbell sound outputdevice controller and the doorbell switch.

In some embodiments of the fourth aspect, the current sense circuitryincludes: (a) an electrical conductor configured to be electricallycoupled to the doorbell switch, and (b) a Hall effect sensor configuredto sense a magnetic field generated by electrical current flowingthrough the electrical conductor.

In a fifth aspect, a method for operating a doorbell sound output deviceincludes (a) generating an activation signal at a doorbell switch inresponse to a user command to activate the doorbell sound output device,(b) receiving the activation signal at a doorbell sound output devicecontroller external to the doorbell switch, and (c) in response toreceiving the activation signal at the doorbell sound output devicecontroller, enabling flow of electrical current between the doorbellsound output device controller and the doorbell sound output device.

In some embodiments of the fifth aspect, the method further includestransmitting the activation signal from the doorbell switch to thedoorbell sound output device controller via wiring electrically couplingthe doorbell switch to the doorbell sound output device controller.

In some embodiments of the fifth aspect, the method further includeselectrically powering the doorbell switch via the wiring electricallycoupling the doorbell switch to the doorbell sound output devicecontroller while transmitting the activation signal from the doorbellswitch to the doorbell sound output device controller.

In some embodiments of the fifth aspect, generating the activationsignal at the doorbell switch includes generating a tone selected fromthe group consisting of a simple tone and a modulated tone.

In some embodiments of the fifth aspect, generating the activationsignal at the doorbell switch includes changing electrical currentflowing through the wiring electrically coupling the doorbell switch tothe doorbell sound output device controller.

In some embodiments of the fifth aspect, the method further includesgenerating video image data representing a scene proximate to thedoorbell switch.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram illustrating a prior-art doorbell systemincluding a mechanical doorbell sound output device.

FIG. 2 is a schematic diagram illustrating a prior-art doorbell systemincluding an electronic doorbell sound output device.

FIG. 3 is a schematic diagram illustrating a prior-art doorbell systemincluding a shunt device.

FIG. 4 is a schematic diagram illustrating a doorbell system including adoorbell sound output device controller, according to an embodiment.

FIG. 5 is a schematic diagram illustrating a doorbell switch including atransmitter, according to an embodiment.

FIG. 6 is a schematic diagram illustrating a doorbell sound outputdevice controller including a receiver, according to an embodiment.

FIG. 7 is a schematic diagram illustrating a doorbell switch includingperturbation circuitry, according to an embodiment.

FIG. 8 is a schematic diagram illustrating a doorbell sound outputdevice controller including current sense circuitry, according to anembodiment.

FIG. 9 is an example graph of magnitude of current through an electricalconductor of the FIG. 8 doorbell sound output device controller when aperturbation switching device is open, according to an embodiment.

FIG. 10 is an example graph of magnitude of current through anelectrical conductor of the FIG. 8 doorbell sound output devicecontroller when a perturbation switching device is closed, according toan embodiment.

FIG. 11 is a schematic diagram illustrating a doorbell system includinga doorbell sound output device controller with a diode deviceelectrically coupled in parallel with a switching device, according toan embodiment.

FIG. 12 is a schematic diagram illustrating a doorbell system where adoorbell sound output device controller includes a switching deviceimplemented by two metal oxide semiconductor field effect transistors,according to an embodiment.

FIG. 13 is a schematic diagram illustrating a doorbell switch configuredas a video doorbell, according to an embodiment.

FIG. 14 is a schematic diagram illustrating a doorbell system where adoorbell sound output device and a doorbell sound output devicecontroller are integrated in a common package, according to anembodiment.

FIG. 15 is a schematic diagram illustrating a doorbell system where adoorbell sound output device, a doorbell sound output device controller,and a transformer are integrated in a common package, according to anembodiment.

FIG. 16 is a flowchart illustrating a method for operating a doorbellsound output device, according to an embodiment.

FIG. 17 is a functional block diagram illustrating a system forstreaming and storing audio/video (A/V) content captured by a device,according to an embodiment.

FIG. 18 is a flowchart illustrating a process for streaming and storingA/V content from the device of FIG. 17, according to an embodiment.

FIG. 19 is a functional block diagram of a client device on which thepresent embodiments may be implemented according to various aspects ofthe present disclosure.

FIG. 20 is a functional block diagram of a system on which the presentembodiments may be implemented according to various aspects of presentdisclosure.

FIG. 21 is a front perspective view of the device of FIG. 17 implementedas a doorbell, in an embodiment.

FIG. 22 is a schematic diagram illustrating a doorbell system includinga doorbell sound output device controller with a switching deviceincluding a triac, according to an embodiment.

FIG. 23 is a schematic diagram illustrating a doorbell sound outputdevice controller including filtering circuitry, according to anembodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Some modern doorbell switches consume significant electrical power andtherefore must be used with a shunt device to achieve proper operation.For example, FIG. 3 illustrates a prior-art doorbell system 300including a transformer 302, a doorbell switch 304, a mechanicaldoorbell sound output device 306, and a shunt device 308. A primarywinding 310 of the transformer 302 is electrically coupled to an ACelectrical power source (not shown), and a secondary winding 312 of thetransformer 302 is electrically coupled in series with the doorbellswitch 304 and the mechanical doorbell sound output device 306. Thedoorbell switch 300 includes a switching device 314 and a power supply316. The switching device 314 is electrically coupled in series with themechanical doorbell sound output device 306. The switching device 314 isnormally open, and closing the switching device 314 enables electricalcurrent to flow through the mechanical doorbell sound output device 306,thereby energizing the mechanical doorbell sound output device 306 andcausing it to emit at least one tone. The power supply 316 electricallypowers the doorbell switch 304, and the power supply 316 receives inputelectrical power from the transformer 302 via wiring 318 and themechanical doorbell sound output device 306.

The shunt device 308 increases electrical power available to thedoorbell switch 304. In particular, solenoid DC resistance of themechanical doorbell sound output device 306 is typically about 8 to 12ohms. This resistance significantly reduces available voltage and powerfrom the transformer 302 to the doorbell switch 304, and the doorbellswitch 304 may consume up to a few watts of power, depending on theoperational state of the doorbell switch 304. Consequently, the doorbellswitch 304 would likely not receive sufficient electrical power if theshunt device 308 were not present.

The shunt device 308 is electrically coupled in parallel with themechanical doorbell sound output device 306, and the shunt device 308includes a normally-closed switching device 320 and a current limitingresistor 322 electrically coupled in series. The shunt device 308bypasses the mechanical doorbell sound output device 306 when thenormally-closed switching device 320 is closed, thereby enabling thedoorbell switch 304 to receive a greater voltage magnitude and a greaterelectrical power magnitude than would otherwise be possible if the shuntdevice 308 were not present. The shunt device 308 further includescontrol circuitry (not shown) to detect an increase in current flowingthrough the shunt device 308 in response to closing of the switchingdevice 314, and the control circuitry causes the switching device 320 toopen in response to the detected current increase. Opening the switchingdevice 320 enables nearly all available power from the transformer 302to be provided to the mechanical doorbell sound output device 306. Thus,the shunt device 308 enables each of the doorbell switch 304 and themechanical doorbell sound output device 306 to receive sufficientelectrical power for proper operation.

However, embodiments described herein include the realization that thedoorbell system 300 has a significant negative aspect. In particular,closure of the switching device 314 during activation of the mechanicaldoorbell sound output device 306 electrically bypasses the power supply316 of the doorbell switch 304. Consequently, the doorbell switch 304cannot receive electrical power from the transformer 302 during thistime. Thus, if the doorbell switch 304 is to operate continuously, abattery or other energy storage device must be provided to power thedoorbell switch 304 while the switching device 314 is closed.

There are many disadvantages to powering the doorbell switch 304 from abattery or other energy storage device. For example, a battery has alimited lifespan, and battery performance is typically significantlyreduced at cold temperatures. Indeed, commercial grade, rechargeableLiPo (lithium polymer) batteries are typically not allowed to charge atbattery temperatures below 0° C., due to issues of battery damage andlifetime degradation. Doorbell switches are typically mounted outside ofa building where weather conditions can easily be such that LiPo batterycharging is not recommended. Additionally, presence of a rechargeablebattery in the doorbell switch 304 typically requires battery managementhardware and/or firmware, thus making the doorbell switch 304 relativelycomplicated and expensive. Accordingly, a doorbell switch that does notrequire a battery is advantageous over a doorbell switch that doesrequire a battery.

Embodiments described herein include doorbell sound output devicecontrollers, doorbell switches, and associated systems and methods thatat least partially overcome one or more of the problems discussed above.The new doorbell switches include activation circuitry configured togenerate an activation signal in response to a user command to activatea doorbell sound output device, and certain embodiments of the doorbellswitches are capable of continuously operating without a battery orother energy storage device. The doorbell sound output devicecontrollers include control circuitry configured to control a switchingdevice to enable flow of electrical current between the doorbell soundoutput device controller and the doorbell sound output device inresponse to receiving the activation signal.

FIG. 4 illustrates a doorbell system 400 including an embodiment of thepresent doorbell switches and an embodiment of the present doorbellsound output device controller. The doorbell system 400 includes atransformer 402, a doorbell switch 404, a doorbell sound output device406, and a doorbell sound output device controller 408 external to thedoorbell switch 404. The doorbell sound output device 406 is, forexample, a mechanical doorbell sound output device or an electronicdoorbell sound output device. A primary winding 410 of the transformer402 is electrically coupled to an AC electrical power source (notshown), and a secondary winding 412 of the transformer 402 iselectrically coupled to the doorbell switch 404 and the doorbell soundoutput device controller 408 via wiring 414. Each of the doorbell switch404 and the doorbell sound output device controller 408 are electricallycoupled in parallel with the second winding 412 via the wiring 414.

The doorbell switch 404 includes a user input device 416, activationcircuitry 418, and power supply circuitry 420. The user input device 416is configured to receive a user command to activate the doorbell soundoutput device 406. In certain embodiments, the user input device 416 isa touch-sensitive input device, such as a push-button switch or acapacitive sensing device, which receives a user command to activate thedoorbell sound output device 406 by a user touching the user inputdevice. Additionally, or alternatively, in some embodiments, the userinput device 416 is configured to receive a user command to activate thedoorbell sound output device 406 by detecting presence of a user in thevicinity of the doorbell switch 404, such as from image capture of theuser, motion of the user, and/or infrared energy emitting by the user.

The activation circuitry 418 is configured to generate an activationsignal in response to the user input device 416 receiving the usercommand to activate the doorbell sound output device 406. In particularembodiments, the activation circuitry 418 is configured to transmit theactivation signal to the doorbell sound output device controller 408 viathe wiring 414 electrically coupling the doorbell switch 404 to thedoorbell sound output device controller 408, such as discussed belowwith respect to FIGS. 5 and 7. In some other embodiments, the activationcircuitry 418 is configured to transmit the activation signal to thedoorbell sound output device controller 408 using another technique,such as using radio frequency transmission or optical transmission.

The power supply circuitry 420 is configured to receive input electricalpower from the transformer 402 via the wiring 414 electrically couplingthe doorbell switch 404 to the doorbell sound output device controller408 and the transformer 402. Additionally, the power supply circuitry420 is configured to electrically power the doorbell switch 404. In someembodiments, the power supply circuitry 420 includes a switching powerconverter and/or a linear regulator, while in some other embodiments,the power supply circuitry 420 rectifies and filters AC voltage fromsecondary winding 412 to provide bulk power to doorbell switch 404.

The doorbell sound output device controller 408 includes a switchingdevice 422 and control circuitry 424. The switching device 422 isconfigured to control flow of electrical power from the transformer 402to the doorbell sound output device 406. The switching device 422includes, for example, a triac, one or more transistors, or anelectro-mechanical relay. For example, FIG. 22 illustrates an embodimentof the doorbell system 400 where the switching device 422 includes atriac 2222. In particular embodiments, the switching device 422 includestwo metal oxide semiconductor field effect transistors (MOSFETs)electrically coupled in series such that the respective body diodes ofthe MOSFETs have opposing orientations, to prevent both body diodes frombeing simultaneously forward-biased. The control circuitry 424 isconfigured to receive the activation signal from the doorbell switch404, and control the switching device 422 to enable flow of electricalcurrent from the transformer 402 to the doorbell sound output device 406in response to receiving the activation signal from the doorbell switch404. Thus, the doorbell sound output device 406 emits at least one tonein response to the user input device 416 receiving the user command toactivate the doorbell sound output device 406.

FIG. 5 illustrates a doorbell switch 504, which is one embodiment of thedoorbell switch 404. The doorbell switch 504 includes a user inputdevice 516, activation circuitry 518, and power supply circuitry 520,which are embodiments of the user input device 416, the activationcircuitry 418, and the power supply circuitry 420, respectively. Theactivation circuitry 518 includes a transmitter 526 configured togenerate an activation signal in the form of a tone on the wiring 414electrically coupling the doorbell switch to the doorbell sound outputdevice controller, to transmit the activation signal to the doorbellsound output device controller. In some embodiments, the activationcircuitry 518 generates the tone on the wiring 414 as a differentialsignal, to promote distinguishing the tone from spurious noise. In someembodiments, the tone generated by the transmitter 526 is a simple tone,e.g., a tone composed of one or more signals of constant frequency andmagnitude. In some other embodiments, the tone generated by thetransmitter 526 is a modulated tone, such as to facilitatedistinguishing the tone from spurious noise and/or to enable the tone tocarry information to the doorbell sound output device controller.

The activation circuitry 518 and the power supply circuitry 520 areelectrically coupled in parallel with the wiring 414, such thatoperation of the activation circuitry 518 does not interfere withoperation of the power supply circuitry 520. Thus, the power supplycircuitry 520 is capable of powering the doorbell switch 504 even whenthe activation circuitry 518 is transmitting an activation signal to thedoorbell sound output device controller. Consequently, the doorbellswitch 504 can continuously operate without an energy storage device.

FIG. 6 illustrates a doorbell sound output device controller 608, whichis one embodiment of doorbell sound output device controller 408. Thedoorbell sound output device controller 608 is capable of use with thedoorbell switch 504 of FIG. 5. The doorbell sound output devicecontroller 608 includes a switching device 622 and control circuitry624, which are embodiments of the switching device 422 and the controlcircuitry 424, respectively. Control circuitry 624 includes a receiver628, a processor 630, a power supply 632, and driver circuitry 634. Thereceiver 628 is configured to receive the tone generated the doorbellswitch 504 via the wiring 414 electrically coupling the doorbell switch504 to the doorbell sound output device controller 608. In someembodiments, the processor 630 may comprise a microprocessor, or anothertype of processor, such as an ASIC (application-specific integratedcircuit). In some embodiments, the receiver 628 includes a phase-lockedloop configured to detect a signal having the frequency of the tonegenerated by the doorbell switch 504. Additionally, in some embodiments,the receiver 628 includes a bandpass filter and a peak detector tofacilitate detecting the tone generated by the doorbell switch 504.

The processor 630 receives detected signals from the receiver 628, andthe processor 630 filters the tone generated by the doorbell switch 504from other signals received by the control circuitry 624. Thus, theprocessor 630 promotes immunity of the control circuitry 624 to spuriousnoise. In some embodiments, the processor 630 is further configured toamplify and digitize signals detected by the receiver 628.

The driver circuitry 634 is configured to electrically interface theswitching device 622 with the processor 630. For example, in embodimentswhere the switching device 622 includes one or more MOSFETs, the drivercircuitry 634 is configured to drive the gates of the one or moreMOSFETs, to switch the MOSFETs between their conductive andnon-conductive states. In particular embodiments, the driver circuitry634 is configured provide galvanic isolation between the controlcircuitry 634 and the switching device 622, such as via optical ormagnetic coupling. The processor 630 controls the driver circuitry 634to cause the switching device 622 to operate in its conductive state inresponse to the processor 630 detecting the tone generated by thedoorbell switch 504, thereby causing the doorbell sound output device406 to emit at least one tone.

In some embodiments, the processor 630 is configured to cause theswitching device 622 to operate in its conductive state for a fixedduration in response to the control circuitry 624 receiving the tonefrom the doorbell switch 504. In some other embodiments, the processor630 is configured to enable adjustment of a duration that the switchingdevice 622 operates in its conductive state in response to the controlcircuitry 624 receiving the tone from the doorbell switch 504. Forexample, in a particular embodiment, the processor 630 is configured toreceive a configuration command, such as from the doorbell switch 504 orfrom one or more configuration switches (not shown) in the doorbellsound output device controller 608, to enable adjustment of the durationthat the switching device 622 operates in its conductive state inresponse to the control circuitry 624 receiving the tone from thedoorbell switch 504.

The power supply 632 receives electrical power from the transformer 402via wiring 414, and the power supply 632 is configured to provideelectrical power to the control circuitry 624. In some embodiments, thepower supply 632 includes a switching power converter and/or a linearregulator, while in some other embodiments, the power supply 632rectifies and filters AC voltage from secondary winding 412.

The control circuitry 624 could be modified without departing from thescope of the present embodiments. For example, in some alternateembodiments, the processor 630 is replaced with other analog and/ordigital circuitry configured to act as filtering circuitry. FIG. 23illustrates a doorbell sound output device controller similar to thedoorbell sound output device controller 608 but where the processor 630is replaced with filtering circuitry 2330. As another example, in someother alternate embodiments, the processor 630 is omitted and thereceiver 628 is directly coupled to the driver circuitry 634.

FIG. 7 illustrates a doorbell switch 704, which is another embodiment ofthe doorbell switch 404. The doorbell switch 704 includes a user inputdevice 716, activation circuitry 718, and power supply circuitry 720,which are embodiments of the user input device 416, the activationcircuitry 418, and the power supply circuitry 420, respectively. Theactivation circuitry 718 includes perturbation circuitry 728 configuredto generate an activation signal on the wiring 414 electrically couplingthe doorbell switch to the doorbell sound output device controller bychanging electrical current flowing through the wiring, in response tothe user input device 716 receiving a command to activate the doorbellsound output device 406.

The perturbation circuitry 728 includes a normally-open perturbationswitching device 730 and an impedance device 732 electrically coupled inseries across the wiring 414 electrically coupling the doorbell switch704 to the doorbell sound output device controller. The impedance valueof the impedance device 732 is chosen to be sufficiently low to enabledetection of the perturbation switching device 730 being closed throughan increase in current flowing between the doorbell switch 704 and adoorbell sound output device controller. However, the impedance value ofthe impedance device 732 should not be so low as to dissipate excessivepower when the perturbation switching device 730 is closed. Although theimpedance device 732 is illustrated as a single resistor, the impedancedevice 732 can take other forms, such as a network of resistors and/orone or more complex impedance devices without departing from the scopeof the present embodiments. The perturbation circuitry 728 is configuredto close the perturbation switching device 730 in response to the userinput device 716 receiving a command to activate the doorbell soundoutput device 406, thereby changing (increasing) the magnitude of thecurrent flowing through the wiring 414 between the doorbell switch 704the doorbell sound output device controller.

The activation circuitry 718 and the power supply 720 are electricallycoupled in parallel with the wiring 414, and an impedance value of theimpedance device 732 is sufficiently high such that closing of theperturbation switching device 730 does not degrade operation of thepower supply circuitry 720. Consequently, operation of the activationcircuitry 718 does not interfere with operation of the power supplycircuitry 720, and the power supply circuitry 720 is capable of poweringthe doorbell switch 704 even while the activation circuitry 718 istransmitting an activation signal to a doorbell sound output devicecontroller. Consequently, the doorbell switch 704 can continuouslyoperate without an energy storage device.

FIG. 8 illustrates a doorbell sound output device controller 808, whichis another embodiment of the doorbell sound output device controller408. The doorbell sound output device controller 808 is capable of usewith the doorbell switch 704 of FIG. 7. The doorbell sound output devicecontroller 808 includes a switching device 822 and control circuitry824, which are embodiments of the switching device 422 and the controlcircuitry 424, respectively. The control circuitry 824 includes currentsense circuitry 828, a conditioner 830, a processor 832, drivercircuitry 834, and a power supply 836. In some embodiments, theprocessor 832 may comprise a microprocessor, or another type ofprocessor, such as an ASIC (application-specific integrated circuit).

The current sensing circuitry 828 is configured the receive theactivation signal from the doorbell switch 704 via a change inelectrical current flowing between the doorbell sound output devicecontrol 808 and the doorbell switch 704. In the illustrated embodiment,current sense circuitry 828 includes an electrical conductor 838 and aHall effect sensor 840. The electrical conductor 838 is configured to beelectrically coupled to the doorbell switch 704 such that electricalcurrent flowing between the doorbell switch 704 and the doorbell soundoutput device controller 808 flows through the electrical conductor 838.Therefore, electrical current flowing through the electrical conductor838 represents the electrical current flowing between the doorbellswitch 704 and the doorbell sound output device controller 808. Incertain embodiments, the electrical conductor 838 forms a small numberof turns, such as only a single turn, to minimize length and associatedresistance of the electrical conductor 838. The Hall effect sensor 840is configured to sense a magnetic field generated by electrical currentflowing through the electrical conductor 838 and generate a correspondsignal.

The use of the electrical conductor 838 and the Hall effect sensor 840to detect the activation signal generated by the doorbell switch 704 hasadvantages. For example, the electrical conductor 838 can be embodied asa single loop of copper wire or metal film integrated within the packageof an integrated circuit (IC), to promote low cost, low voltage dropacross the current sensing circuitry 828, and/or ease of manufacturingthe current sensing circuitry. Additionally, the magnetic couplingbetween electrical conductor 838 and the Hall effect sensor 840 mayprovide galvanic isolation between DC-powered components of the controlcircuitry 824 and AC powered circuitry.

The conditioner 830 conditions the signal generated by the Hall effectsensor 840 to a form that is compatible with the processor 832. Forexample, in some embodiments, the conditioner 830 sufficiently amplifiesthe signal generated by the Hall effect sensor 840 so that the signal isdetectable by the processor 832. In some embodiments, the processor 832is further configured to amplify and digitize signals detected by theconditioner 830. The processor 832 is configured to detect the change inelectrical current flowing between the doorbell sound output devicecontroller 808 and the doorbell switch 704, which represents theactivation signal, from the conditioned signal via generated by theconditioner 830.

For instance, in some embodiments, the processor 832 is configured todetect the activation signal in response to a change in amount of timethat magnitude of the electrical current flowing through the electricalconductor 838 is zero, which is equivalent to a change in amount of timethat the magnitude of the electrical current flowing between thedoorbell sound output device controller 808 and the doorbell switch 704is zero. To help appreciate how magnitude of electrical current can bechanged by the perturbation circuitry 728, consider the examples ofFIGS. 9 and 10. FIG. 9 is an example graph of magnitude of currentthrough the electrical conductor 838 versus time when the switchingdevice 730 is open, and FIG. 10 is an example graph of current throughthe electrical conductor 838 versus time when the switching device 730is closed. As illustrated in FIG. 9, magnitude of current through theelectrical conductor 838 is zero more than 50% of the time when theswitching device 730 is open, e.g., when the activation circuitry 718 isnot generating an activation signal. In contrast, when the switchingdevice 730 is closed, e.g., when the activation circuitry 718 isgenerating an activation signal, magnitude of current through theelectrical conductor 838 is zero only twice per cycle of AC voltageacross the wiring 414. The processor 832 detects such decrease in amountof time that magnitude of current through the electrical conductor 838is zero as an activation signal from the doorbell switch 704.

The small magnitude of current through the impedance device 732 relativeto the scale of the FIG. 10 graph causes portions of the FIG. 10 graphto appear linear. Such portions of the graph are actually sinusoidal,but such sinusoidal characteristic is not perceptible in the FIG. 10graph.

The driver circuitry 834 is configured to interface the switching device822 with the processor 832 in a manner analogous to that of the drivercircuitry 634 of FIG. 6. The processor 832 controls the driver circuitry834 to cause the switching device 822 to operate in its conductive statein response to the processor 832 detecting the activation signalgenerated by the doorbell switch 704 from a change in electrical currentflowing through the electrical conductor 838, thereby causing thedoorbell sound output device 406 to emit at least one tone.

In some embodiments, the processor 832 is configured to cause theswitching device 822 to operate in its conductive state for a fixedduration in response to the control circuitry 824 receiving anactivation signal from doorbell switch 704. In some other embodiments,the processor 832 is configured to enable adjustment of a duration thatthe switching device 822 operates in its conductive state in response tothe control circuitry 824 receiving the activation signal from thedoorbell switch 704. For example, in a particular embodiment, theprocessor 832 is configured to receive a configuration command, such asfrom the doorbell switch 704 or from one or more configuration switches(not shown) in the doorbell sound output device controller 808, toenable adjustment of the duration that the switching device 822 operatesin its conductive state in response to the control circuitry 824receiving the activation signal from the doorbell switch 704.

The power supply 836 receives electrical power from the transformer 402via the wiring 414, and the power supply 836 is configured to provideelectrical power to the control circuitry 824. In some embodiments, thepower supply 832 includes a switching power converter and/or a linearregulator, while in some other embodiments, the power supply 832rectifies and filters AC voltage from the secondary winding 412.

The control circuitry 824 could be modified without departing from thescope of the present embodiments. For example, in some alternateembodiments, the processor 832 is replaced with other analog and/ordigital circuitry configured to act as filtering circuitry. As anotherexample, in some other alternate embodiments, the processor 832 isomitted and the conditioner 830 is directly coupled to the drivercircuitry 834. As another example, in certain alternate embodiments, thecurrent sense circuitry 828 is implemented in a different manner thanthat illustrated in FIG. 8, such as by use of a current sense resistorin place of the electrical conductor 838 and the Hall effect sensor 840.

The doorbell sound output device controllers herein could be configuredto support an electronic doorbell sound output device. For example, FIG.11 illustrates a doorbell system 1100, which is similar to the doorbellsystem 400 of FIG. 4, but where the doorbell sound output devicecontroller 408 is replaced with a doorbell sound output devicecontroller 1108. The doorbell sound output device controller 1108 issimilar to the doorbell sound output device controller 408, but furtherincludes a diode device 1126 electrically coupled in parallel with theswitching device 422. The diode device 1126 provides a path for DCelectrical current between the doorbell sound output device controller1108 and the doorbell sound output device 406, such as in cases wherethe doorbell sound output device 406 is an electronic doorbell soundoutput device. The polarity of the diode device 1126, e.g., thelocations of its anode (A) and cathode (K) with respect to othercomponents of the doorbell sound output device controller 1108, could bereversed without departing from the scope of the present embodiments.

In some embodiments, the diode device 1126 is implemented by a singlesemiconductor diode, such as illustrated in FIG. 11. In some otherembodiments, the diode device 1126 is implemented by multiplesemiconductor diodes electrically coupled in series, such as to achievea high breakdown voltage rating. In yet some other embodiments, thediode device 1126 is implemented by one or more transistors, or by bodydiodes of one or more transistors.

For example, FIG. 12 illustrates a doorbell system 1200, which is anembodiment of the doorbell system 1100 where the doorbell sound outputdevice controller 1108 is implemented as a doorbell sound output devicecontroller 1208. The switching device 422 of the doorbell sound outputdevice controller 1108 is implemented by two n-channel, enhancementMOSFETs 1222 and 1223 electrically coupled in series with opposingorientations, in the doorbell sound output device controller 1208. Thecontrol circuitry 424 drives the gates of the MOSFETs 1222 and 1223 toswitch the MOSFETs between their respective conductive andnon-conductive states to control flow of electrical current between thedoorbell sound output device controller 1208 and the doorbell soundoutput device 406. The control circuitry 424 is further configured toreceive a configuration command, such as from the doorbell switch 404 orfrom configuration switches (not shown) in the doorbell sound outputdevice controller 1208, to configure the doorbell sound output devicecontroller 1208 for use with an electronic doorbell sound output device.In particular, the control circuitry 424 causes the MOSFET 1223 tocontinuously operate in its conductive state in response to theconfiguration command, such that a body diode 1226 of the MOSFET 1222provides a path for direct current between the doorbell sound outputdevice controller 1208 and the doorbell sound output device 406.

The configurations of the transistors in doorbell sound output devicecontroller 1208 could be varied with departing from the scope of thepresent embodiments. For example, the MOSFETs 1222 and 1223 could bereplaced with p-channel MOSFETs with appropriate changes to the controlcircuitry 424.

Although the doorbell switches 404, 504, and 704 are illustrated asincluding only a user input device, activation circuitry, and powersupply circuitry for illustrative simplicity, any of these doorbellswitches could include additional components without departing from thescope of the present embodiments. For example, FIG. 13 illustrates adoorbell switch 1300, which is an embodiment of the doorbell switch 404configured as a video doorbell. The doorbell switch 1300 represents anaudio/video (A/V) recording and communication device (also referred toas a security device). The doorbell switch 1300 includes powermanagement circuitry 1302, an audio coder-decoder (codec) 1304, a modem1306, a processor 1308, a memory 1310 communicatively coupled to theprocessor 1308, a video camera 1312, a microphone 1314, and a speaker1316, as well as an instance of the user input device 416, theactivation circuitry 418, and the power supply circuitry 420. The powermanagement circuitry 1302 receives bulk power from the power supplycircuitry 420 and conditions the bulk power for use by the doorbellswitch 1300. For example, in some embodiments, the power managementcircuitry 1302 regulates bulk power from the power supply circuitry 420.Electrical power from the power management circuitry 1302 is distributedto other components of the doorbell switch 1300 via an electrical bus1318. The power management circuitry 1302 may be omitted in cases wherebulk power from the power supply circuitry 420 is sufficiently regulatedfor use within the doorbell switch 1300.

The modem 1306 is configured to enable the doorbell switch 1300 tocommunicate with an external system. For example, in some embodiments,the modem 1306 is a wireless modem, such as for use with a WiFi network.As another example, in some other embodiments, the modem 1306 isconfigured for use with an optical network or a wired network.Communications via the modem 1306 may also include links to any of avariety of wireless networks, including WAP (Wireless ApplicationProtocol), GPRS (General Packet Radio Service), GSM (Global System forMobile Communication), LTE, VoLTE, LoRaWAN, LPWAN, RPMA, LTE Cat-“X”(e.g., LTE Cat 1, LTE Cat 0, LTE CatM1, LTE Cat NB1), CDMA (CodeDivision Multiple Access), TDMA (Time Division Multiple Access), FDMA(Frequency Division Multiple Access), and/or OFDMA (Orthogonal FrequencyDivision Multiple Access) cellular phone networks, GPS, CDPD (cellulardigital packet data), RIM (Research in Motion, Limited) duplex pagingnetwork, Bluetooth radio, or an IEEE 802.11-based radio frequencynetwork. The modem 1306 may further include or interface with any one ormore of the following: RS-232 serial connection, IEEE-1394 (Firewire)connection, Fibre Channel connection, IrDA (infrared) port, SCSI (SmallComputer Systems Interface) connection, USB (Universal Serial Bus)connection, or other wired or wireless, digital or analog, interface orconnection, mesh or Digi® networking.

The video camera 1312 is configured to generate video image datarepresenting a scene proximate to the doorbell switch 1300. Inparticular embodiments, the video camera 1312 includes a complementarymetal oxide semiconductor (CMOS) image sensor and supporting circuitry.The video camera 1312 in some embodiments may include an infrared lightsource and a selectively-activated infrared filter, to facilitategenerating video image data in both light and dark ambient conditions.

The audio codec 1304 is configured to interface the microphone 1312 andthe speaker 1314, which are each analog devices, with digital circuitryin the doorbell switch 1300, such with the processor 1308. Accordingly,the audio codec 1304 is configured to convert data between digital formand analog form, and vice versa. The microphone 1314 is configured togenerate sound data representing sound proximate to the doorbell switch1300, and the speaker 1316 is configured to generate sound datarepresenting sound in response to a signal received by the doorbellswitch 1300 from a device external to the doorbell switch 1300.

The processor 1308 is configured to execute instructions in the form ofsoftware and/or firmware stored in the memory 1310 to control operationof the doorbell switch 1300. For example, in some embodiments, theprocessor 1308 is configured to enable a remote user to view a sceneproximate to the doorbell switch 1300 via the video camera 1312 and themodem 1306. As another example, in certain embodiments, the processor1308 is configured to enable a remote user to listen to sound proximateto the doorbell switch 1300 via the microphone 1314, the audio code1304, and the modem 1306. As yet another example, in particularembodiments, the processor 1308 is configured to enable a remote user tomake an audio announcement at the doorbell switch 1300 via the speaker1316, the audio codec 1304, and the modem 1306.

Any of the doorbell switches 404, 504, and 704 could be integrated witha doorbell sound output device without departing from the scope of thepresent embodiments. For example, FIG. 14 illustrates a doorbell system1400, which is similar to the doorbell system 400 of FIG. 4, but wherethe doorbell sound output device 406 and the doorbell sound outputdevice controller 408 are integrated in a common package 1402.Additionally, the transformer 402 could be co-packaged the doorbellsound output device and the doorbell sound output device controller. Forexample, FIG. 15 illustrates a doorbell system 1500, which is similar tothe doorbell system 400 of FIG. 4, but where the doorbell sound outputdevice 406, the doorbell sound output device controller 408, and thetransformer 402 are integrated in a common package 1502.

FIG. 16 illustrates a method 1600 for operating a doorbell sound outputdevice in accordance with various aspects of the present embodiments. Atblock 1602, an activation signal is generated at a doorbell switch inresponse a user command to activate the doorbell sound output device. Inone example of block 1602, the transmitter 526 (FIG. 5) generates a toneon the wiring 414 in response to the user input device 516 receiving auser command to activate doorbell sound output device 406. In anotherexample of block 1602, the perturbation switching device 730 (FIG. 7)closes in response to the user input device 716 receiving a user commandto activate the doorbell sound output device 406.

At block 1604, the activation signal is received at a doorbell soundoutput device controller external to the doorbell switch. In one exampleof block 1604, the receiver 628 (FIG. 6) receives the activation signalvia a tone from the doorbell switch 504. In another example of block1604, the current sensing circuitry 828 (FIG. 8) receives the activationsignal from the doorbell switch 704 via a change in electrical currentflowing between the doorbell sound output device controller 808 and thedoorbell switch 704.

At block 1606, flow of electrical current between the doorbell soundoutput device controller and the doorbell sound output device is enabledin response to receiving the activation signal at the doorbell soundoutput device controller. In one example of block 1606, the processor630 (FIG. 6) controls the driver circuitry 634 to cause the switchingdevice 622 to operate in its conductive state in response to thereceiver 628 receiving an activation signal via a tone from the doorbellswitch 504. As another example of block 1606, the processor 832 (FIG. 8)controls the driver circuitry 834 to cause the switching device 822 tooperate in its conductive state in response to the current sensingcircuitry 828 receiving the activation signal from the doorbell switch704 via a change in electrical current flowing between the doorbellsound output device controller 808 and the doorbell switch 704.

A/V Recording and Communication Device

With reference to FIG. 17, the present embodiments include an A/Vrecording and communication device 1700, also known as a security device1700. The A/V recording and communication device 1700 is an embodimentof the doorbell switches 404, 504, 704, and 1300, discussed above. Anexample A/V recording and communication security camera may includesubstantially all of the structure and/or functionality of the doorbellsdescribed herein, but without a front button and related components.

The A/V recording and communication device 1700 may be located near theentrance to a structure (not shown), such as a dwelling, a business, astorage facility, etc. The A/V recording and communication device 1700includes a camera 1702, a microphone 1704, and a speaker 1706. Thecamera 1702 may include, for example, a high definition (HD) videocamera, such as one configured for capturing video images at an imagedisplay resolution of 720p, or 1080p, or better. The camera 1702 may bean embodiment of the video camera 1312 discussed above. While not shown,the A/V recording and communication device 1700 may also include otherhardware and/or components, such as a housing, a communication module(e.g., the modem 1306 discussed above, which may facilitate wired and/orwireless communication with other devices), one or more motion sensors(and/or other types of sensors), a button, etc. The A/V recording andcommunication device 1700 may further include similar componentry and/orfunctionality as the wireless communication doorbells described in U.S.Pat. No. 9,584,775 and US Patent Application Number 2015/0022618(application Ser. No. 14/334,922), respectively.

With further reference to FIG. 17, the A/V recording and communicationdevice 1700 communicates with a user's network 1710, which may be forexample a wired and/or wireless network. If the user's network 1710 iswireless, or includes a wireless component, the network 1710 may be aWi-Fi network compatible with the IEEE 802.11 standard and/or otherwireless communication standard(s). The user's network 1710 is connectedto another network 1712, which may include, for example, the Internetand/or a public switched telephone network (PSTN). As described below,the A/V recording and communication device 1700 may communicate with theuser's client device 1714 via the user's network 1710 and the network1712 (Internet/PSTN). Alternatively, the A/V recording and communicationdevice 1700 may communicate with the user's client device 1714 via theuser's network 1710 (without the network 1712) and/or via a directconnection, such as over a short-range protocol connection (e.g.,Bluetooth, BTLE, etc.) The user's client device 1714 may include, forexample, a mobile telephone (may also be referred to as a cellulartelephone), such as a smartphone, a personal digital assistant (PDA), oranother communication device. The user's client device 1714 includes adisplay (not shown) and related components configured for displayingstreaming and/or recorded video images. The user's client device 1714may also include a speaker and related components configured forbroadcasting streaming and/or recorded audio, and may also include amicrophone. The A/V recording and communication device 1700 may alsocommunicate with one or more remote storage device(s) 1716 (may bereferred to interchangeably as “cloud storage device(s)”), one or moreservers 1718, and/or a backend API (application programming interface)1720 via the user's network 1710 and the network 1712 (Internet/PSTN).While FIG. 17 illustrates the storage device 1716, the server 1718, andthe backend API 1720 as components separate from the network 1712, it isto be understood that the storage device 1716, the server 1718, and/orthe backend API 1720 may be considered to be components of the network1712.

The network 1712 may be any wireless network or any wired network, or acombination thereof, configured to operatively couple theabove-mentioned modules, devices, and systems as shown in FIG. 17. Forexample, the network 1712 may include one or more of the following: aPSTN, the Internet, a local intranet, a PAN (Personal Area Network), aLAN (Local Area Network), a WAN (Wide Area Network), a MAN (MetropolitanArea Network), a virtual private network (VPN), a storage area network(SAN), a frame relay connection, an Advanced Intelligent Network (AIN)connection, a synchronous optical network (SONET) connection, a digitalT1, T3, E1 or E3 line, a Digital Data Service (DDS) connection, a DSL(Digital Subscriber Line) connection, an Ethernet connection, an ISDN(Integrated Services Digital Network) line, a dial-up port such as aV.90, V.34, or V.34bis analog modem connection, a cable modem, an ATM(Asynchronous Transfer Mode) connection, or an FDDI (Fiber DistributedData Interface) or CDDI (Copper Distributed Data Interface) connection.Furthermore, communications may also include links to any of a varietyof wireless networks, including WAP (Wireless Application Protocol),GPRS (General Packet Radio Service), GSM (Global System for MobileCommunication), LTE, VoLTE, LoRaWAN, LPWAN, RPMA, LTE Cat-“X” (e.g., LTECat 1, LTE Cat 0, LTE CatM1, LTE Cat NB1), CDMA (Code Division MultipleAccess), TDMA (Time Division Multiple Access), FDMA (Frequency DivisionMultiple Access), and/or OFDMA (Orthogonal Frequency Division MultipleAccess) cellular phone networks, GPS, CDPD (cellular digital packetdata), RIM (Research in Motion, Limited) duplex paging network,Bluetooth radio, or an IEEE 802.11-based radio frequency network. Thenetwork 1712 may further include or interface with any one or more ofthe following: RS-232 serial connection, IEEE-1394 (Firewire)connection, Fibre Channel connection, IrDA (infrared) port, SCSI (SmallComputer Systems Interface) connection, USB (Universal Serial Bus)connection, or other wired or wireless, digital or analog, interface orconnection, mesh or Digi® networking.

In certain embodiments, when a person (may be referred tointerchangeably as “visitor”) arrives at the A/V recording andcommunication device 1700, the A/V recording and communication device1700 detects the visitor's presence and begins capturing video imageswithin a field of view of camera 1702. The A/V recording andcommunication device 1700 may also capture audio through microphone1704. The A/V recording and communication device 1700 may detect thevisitor's presence by detecting motion using the camera 1702 and/or amotion sensor, and/or by detecting that the visitor has pressed a frontbutton of the A/V recording and communication device 1700 (for example,when the A/V recording and communication device 1700 is a doorbell).

In response to the detection of the visitor, the A/V recording andcommunication device 1700 sends an alert to the user's client device1714 (FIG. 17) via the user's network 1710 and the network 1712. The A/Vrecording and communication device 1700 also sends streaming video, andmay also send streaming audio, to the user's client device 1714. If theuser answers the alert, two-way audio communication may then occurbetween the visitor and the user through the A/V recording andcommunication device 1700 and the user's client device 1714. The usermay view the visitor throughout the duration of the call, but thevisitor cannot see the user (unless the A/V recording and communicationdevice 1700 includes a display, which it may in certain embodiments).

The video images captured by the camera 1702 of the A/V recording andcommunication device 1700 (and the audio captured by the microphone1704) may be uploaded to the cloud and recorded on the remote storagedevice 1716 (FIG. 17). In some embodiments, the video and/or audio maybe recorded on the remote storage device 1716 even if the user choosesto ignore the alert sent to the user's client device 1714.

With further reference to FIG. 17, the system may further include abackend API 1720 including one or more components. A backend API(application programming interface) may include, for example, a server(e.g., a real server, or a virtual machine, or a machine running in acloud infrastructure as a service), or multiple servers networkedtogether, exposing at least one API to client(s) accessing it. Theseservers may include components such as application servers (e.g.,software servers), depending upon what other components are included,such as a caching layer, or database layers, or other components. Abackend API may, for example, include many such applications, each ofwhich communicate with one another using their public APIs. In someembodiments, the API backend may hold the bulk of the user data andoffer the user management capabilities, leaving the clients to have verylimited state.

The backend API 1720 may include one or more APIs. An API is a set ofroutines, protocols, and tools for building software and applications.An API expresses a software component in terms of its operations,inputs, outputs, and underlying types, defining functionalities that areindependent of their respective implementations, which allowsdefinitions and implementations to vary without compromising theinterface. Advantageously, an API may provide a programmer with accessto an application's functionality without the programmer needing tomodify the application itself, or even understand how the applicationworks. An API may be for a web-based system, an operating system, or adatabase system, and it provides facilities to develop applications forthat system using a given programming language. In addition to accessingdatabases or computer hardware like hard disk drives or video cards, anAPI can ease the work of programming GUI components. For example, an APIcan facilitate integration of new features into existing applications (aso-called “plug-in API”). An API can also assist otherwise distinctapplications with sharing data, which can help to integrate and enhancethe functionalities of the applications.

The backend API 1720 may further include one or more services (alsoreferred to as network services). A network service is an applicationthat provides data storage, manipulation, presentation, communication,and/or other capability. Network services are often implemented using aclient-server architecture based on application-layer network protocols.Each service may be provided by a server component running on one ormore computers (such as a dedicated server computer offering multipleservices) and accessed via a network by client components running onother devices. However, the client and server components can both be runon the same machine. Clients and servers may have a user interface, andsometimes other hardware associated with them.

The A/V recording device 1700 may include any of the features discussedabove with respect to doorbell switches 404, 504, 704, and 1300 tomanage power and control of the doorbell sound output device 406.

FIG. 18 is a flowchart illustrating a process 1800 for streaming andstoring A/V content from the A/V recording and communication device1700, in an embodiment. At block 1801, the A/V recording andcommunication device 1700 detects the visitor's presence and capturesvideo images within a field of view of the camera 1702. The A/Vrecording and communication device 1700 may also capture audio throughthe microphone 1704. As described above, the A/V recording andcommunication device 1700 may detect the visitor's presence by detectingmotion using the camera 1702 and/or a motion sensor, and/or by detectingthat the visitor has pressed a front button of the A/V recording andcommunication device 1700 (for example, when the A/V recording andcommunication device 1700 is a doorbell). Also as described above, thevideo recording/capture may begin when the visitor is detected, or maybegin earlier, as described below.

At block 1802, a communication module of the A/V recording andcommunication device 1700 sends a connection request, via the user'snetwork 1710 and the network 1712, to a device in the network 1712. Forexample, the network device to which the connection request is sent maybe a server such as the server 1718. The server 1718 may include acomputer program and/or a machine that waits for requests from othermachines or software (clients) and responds to them. A server typicallyprocesses data. One purpose of a server is to share data and/or hardwareand/or software resources among clients. This architecture is called theclient-server model. The clients may run on the same computer or mayconnect to the server over a network. Examples of computing serversinclude database servers, file servers, mail servers, print servers, webservers, game servers, and application servers. The term server may beconstrued broadly to include any computerized process that shares aresource to one or more client processes. In another example, thenetwork device to which the request is sent may be an API such as thebackend API 1720, which is described above.

In response to the request, at block 1804 the network device may connectthe A/V recording and communication device 1700 to the user's clientdevice 1714 through the user's network 1710 and the network 1712. Atblock 1806, the A/V recording and communication device 1700 may recordavailable audio and/or video data using the camera 1702, the microphone1704, and/or any other device/sensor available. At block 1808, the audioand/or video data is transmitted (streamed) from the A/V recording andcommunication device 1700 to the user's client device 1714 via theuser's network 1710 and the network 1712. At block 1810, the user mayreceive a notification on the user's client device 1714 with a prompt toeither accept or deny the call.

At block 1812, the process 1800 determines whether the user has acceptedor denied the call. If the user denies the notification, then theprocess 1800 advances to block 1814, where the audio and/or video datais recorded and stored at a cloud server. The session then ends at block1816 and the connection between the A/V recording and communicationdevice 1700 and the user's client device 1714 is terminated. If,however, the user accepts the notification, the process 1800 proceedswith block 1818 where the user communicates with the visitor through theuser's client device 1714 while audio and/or video data captured by thecamera 1702, the microphone 1704, and/or other devices/sensors, isstreamed to the user's client device 1714. At the end of the call, theuser may terminate the connection between the user's client device 1714and the A/V recording and communication device 1700 and the session endsat block 1816. In some embodiments, the audio and/or video data may berecorded and stored at a cloud server (block 1814) even if the useraccepts the notification and communicates with the visitor through theuser's client device 1714.

FIG. 19 is a functional block diagram of a client device 1900 on whichthe present embodiments may be implemented according to various aspectsof the present disclosure. The user's client device 1714 described withreference to FIG. 17 may include some or all of the components and/orfunctionality of the client device 1900. The client device 1900 may be,for example, a smartphone.

The client device 1900 includes a processor 1902, a memory 1904, a userinterface 1906, a communication module 1908, and a dataport 1910. Thesecomponents are communicatively coupled together by an interconnect bus1912. The processor 1902 may include any processor used in smartphonesand/or portable computing devices, such as an ARM processor (a processorbased on the RISC (reduced instruction set computer) architecturedeveloped by Advanced RISC Machines (ARM).). In certain embodiments, theprocessor 1902 includes one or more other processors, such as one ormore microprocessors, and/or one or more supplementary co-processors,such as math co-processors.

The memory 1904 may include both operating memory, such as random accessmemory (RAM), as well as data storage, such as read-only memory (ROM),hard drives, flash memory, or any other suitable memory/storage element.The memory 1904 may include removable memory elements, such as aCompactFlash card, a MultiMediaCard (MMC), and/or a Secure Digital (SD)card. In certain embodiments, the memory 1904 includes a combination ofmagnetic, optical, and/or semiconductor memory, and may include, forexample, RAM, ROM, flash drive, and/or a hard disk or drive. Theprocessor 1902 and the memory 1904 each may be located entirely within asingle device, or may be connected to each other by a communicationmedium, such as a USB port, a serial port cable, a coaxial cable, anEthernet-type cable, a telephone line, a radio frequency transceiver, orother similar wireless or wired medium or combination of the foregoing.For example, the processor 1902 may be connected to the memory 1904 viathe dataport 1910.

The user interface 1906 may include any user interface or presentationelements suitable for a smartphone and/or a portable computing device,such as a keypad, a display screen, a touchscreen, a microphone, and aspeaker. The communication module 1908 is configured to handlecommunication links between the client device 1900 and other, externaldevices or receivers, and to route incoming/outgoing data appropriately.For example, inbound data from the dataport 1910 may be routed throughthe communication module 1908 before being directed to the processor1902, and outbound data from the processor 1902 may be routed throughthe communication module 1908 before being directed to the dataport1910. The communication module 1908 may include one or more transceivermodules configured for transmitting and receiving data, and using, forexample, one or more protocols and/or technologies, such as GSM, UMTS(3GSM), IS-95 (CDMA one), IS-2000 (CDMA 2000), LTE, FDMA, TDMA, W-CDMA,CDMA, OFDMA, Wi-Fi, WiMAX, or any other protocol and/or technology.

The dataport 1910 may be any type of connector used for physicallyinterfacing with a smartphone and/or a portable computing device, suchas a mini-USB port or an IPHONE®/IPOD® 30-pin connector or LIGHTNING®connector. In other embodiments, the dataport 1910 may include multiplecommunication channels for simultaneous communication with, for example,other processors, servers, and/or client terminals.

The memory 1904 may store instructions for communicating with othersystems, such as a computer. The memory 1904 may store, for example, aprogram (e.g., computer program code) adapted to direct the processor1902 in accordance with the present embodiments. The instructions alsomay include program elements, such as an operating system. Whileexecution of sequences of instructions in the program causes theprocessor 1902 to perform the process steps described herein, hard-wiredcircuitry may be used in place of, or in combination with,software/firmware instructions for implementation of the processes ofthe present embodiments. Thus, the present embodiments are not limitedto any specific combination of hardware and software.

System/Device

FIG. 20 is a functional block diagram of a system 2000 on which thepresent embodiments may be implemented according to various aspects ofthe present disclosure. For example, aspects of the system 2000 may bean example of the doorbell switch 404, 504, 704, and 1300, the doorbellsound output device controller 408, 608, 808, 1108, and 1208, and theA/V recording and communication device 1700. The computer system 2000may be embodied in at least one of a personal computer (also referred toas a desktop computer) 2002, a portable computer (also referred to as alaptop or notebook computer) 2004, and/or a server 2006. A server is acomputer program and/or a machine that waits for requests from othermachines or software (clients) and responds to them. A server typicallyprocesses data. The purpose of a server is to share data and/or hardwareand/or software resources among clients. This architecture is called theclient-server model. The clients may run on the same computer or mayconnect to the server over a network. Examples of computing serversinclude database servers, file servers, mail servers, print servers, webservers, game servers, and application servers. The term server may beconstrued broadly to include any computerized process that shares aresource to one or more client processes.

The computer system 2000 may execute at least some of the operationsdescribed above. The computer system 2000 may include at least oneprocessor 2010, a memory 2020, at least one storage device 2030, andinput/output (I/O) devices 2040. Some or all of the components 2010,2020, 2030, 2040 may be interconnected via a system bus 2050. Theprocessor 2010 may be single- or multi-threaded and may have one or morecores. The processor 2010 may execute instructions, such as those storedin the memory 2020 and/or in the storage device 2030. Information may bereceived and output using one or more of the I/O devices 2040.

The memory 2020 may store information, and may be a computer-readablemedium, such as volatile or non-volatile memory. The storage device(s)2030 may provide storage for the computer system 2000, and may be acomputer-readable medium. In various embodiments, the storage device(s)2030 may be one or more of a flash memory device, a hard disk device, anoptical disk device, a tape device, or any other type of storage device.

The I/O devices 2040 may provide input/output operations for thecomputer system 2000. The I/O devices 2040 may include a keyboard, apointing device, and/or a microphone. The I/O devices 2040 may furtherinclude a display unit for displaying graphical user interfaces, aspeaker, and/or a printer. External data may be stored in one or moreaccessible external databases 2060.

The features of the present embodiments described herein may beimplemented in digital electronic circuitry, and/or in computerhardware, firmware, software, and/or in combinations thereof. Featuresof the present embodiments may be implemented in a computer programproduct tangibly embodied in an information carrier, such as a machine-readable storage device, and/or in a propagated signal, for execution bya programmable processor. Embodiments of the present method steps may beperformed by a programmable processor executing a program ofinstructions to perform functions of the described implementations byoperating on input data and generating output.

The features of the present embodiments described herein may beimplemented in one or more computer programs that are executable on aprogrammable system including at least one programmable processorcoupled to receive data and/or instructions from, and to transmit dataand/or instructions to, a data storage system, at least one inputdevice, and at least one output device. A computer program may include aset of instructions that may be used, directly or indirectly, in acomputer to perform a certain activity or bring about a certain result.A computer program may be written in any form of programming language,including compiled or interpreted languages, and it may be deployed inany form, including as a stand-alone program or as a module, component,subroutine, or other unit suitable for use in a computing environment.

Suitable processors for the execution of a program of instructions mayinclude, for example, both general and special purpose processors,and/or the sole processor or one of multiple processors of any kind ofcomputer. Generally, a processor may receive instructions and/or datafrom a read only memory (ROM), or a random access memory (RAM), or both.Such a computer may include a processor for executing instructions andone or more memories for storing instructions and/or data.

Generally, a computer may also include, or be operatively coupled tocommunicate with, one or more mass storage devices for storing datafiles. Such devices include magnetic disks, such as internal hard disksand/or removable disks, magneto-optical disks, and/or optical disks.Storage devices suitable for tangibly embodying computer programinstructions and/or data may include all forms of non-volatile memory,including for example semiconductor memory devices, such as EPROM,EEPROM, and flash memory devices, magnetic disks such as internal harddisks and removable disks, magneto-optical disks, and CD-ROM and DVD-ROMdisks. The processor and the memory may be supplemented by, orincorporated in, one or more ASICs (application-specific integratedcircuits).

To provide for interaction with a user, the features of the presentembodiments may be implemented on a computer having a display device,such as an LCD (liquid crystal display) monitor, for displayinginformation to the user. The computer may further include a keyboard, apointing device, such as a mouse or a trackball, and/or a touchscreen bywhich the user may provide input to the computer.

The features of the present embodiments may be implemented in a computersystem that includes a back-end component, such as a data server, and/orthat includes a middleware component, such as an application server oran Internet server, and/or that includes a front-end component, such asa client computer having a graphical user interface (GUI) and/or anInternet browser, or any combination of these. The components of thesystem may be connected by any form or medium of digital datacommunication, such as a communication network. Examples ofcommunication networks may include, for example, a LAN (local areanetwork), a WAN (wide area network), and/or the computers and networksforming the Internet.

The computer system may include clients and servers. A client and servermay be remote from each other and interact through a network, such asthose described herein. The relationship of client and server may ariseby virtue of computer programs running on the respective computers andhaving a client-server relationship to each other.

Example Embodiments

FIG. 21 is a front perspective view of a doorbell 2130 that representsone example implementation of the security device 1700 of FIG. 17 andthe above discussed doorbell switches 404, 504, 704, and 1300, hereafterreferred to as device 2130. The device 2130 has a housing 2131 thatincludes a backplate 2139, a faceplate 2135 with a button 2133, anoptically-transparent lens 2134A positioned in front of a camera 2134,and an infrared-transparent lens 2132A positioned in front of at leastone motion sensor 2132. The housing 2131 may be further configured withan aperture 2181 to allow sound to enter the housing 2131 for detectionby a microphone. The device 2130 may also include a mounting bracket2142 that couples with the backplate 2139 to facilitate mounting of thedevice 2130 on a flat surface, such as the exterior of a building, suchas a home or office. For example, the mounting bracket 2142 may beselected for mounting to surfaces of various composition, including,without limitation, wood, concrete, stucco, brick, vinyl siding,aluminum siding, etc., with any suitable fasteners, such as screws, orinterference connections, adhesives, etc. The device 2130 may couple tothe mounting bracket 2142 using any suitable fasteners, such as screws,or interference connections, mating hooks and apertures, adhesives, etc.The backplate 2139 may include screw terminals configured to receiveelectrical wires adjacent a mounting surface of the device 2130. Thedevice 2130 may receive electrical power through the screw terminalsand/or the device 2130 may control electrical connectivity of the screwterminals to cause a conventional doorbell to sound if so connected tothe wires.

The faceplate 2135 may extend from the bottom of the device 2130 up tojust below the camera 2134. The faceplate 2135 may be formed of anysuitable material, including, without limitation, metals, such asbrushed aluminum or stainless steel, metal alloys, and plastics, and anycombination thereof. The faceplate 2135 protects the internal contentsof the device 2130 and serves as an exterior front surface of the device2130. The faceplate 2135 may include an aperture 2136A with a flexibletranslucent membrane 2136 for movably holding the button 2133. Thefaceplate 2135 is also formed with at least one speaker grille 2180 toallow sound generated within the housing 2131 to exit. The button 2133and the flexible translucent membrane 2136 may have various profilesthat may or may not match the profile of the faceplate 2135. Theflexible translucent membrane 2136 may include any suitable material,including, without limitation, a transparent silicone, plastic, orrubber, that is configured for allowing light produced within the device2130 to pass through and is sufficiently flexible to allow the button2133 to be pressed. The light may be produced by one or morelight-emitting components, such as light-emitting diodes (LEDs),contained within the device 2130, as further described below. The button2133 and/or the flexible translucent membrane 2136 contacts a switchcover located within the device 2130 when the button 2133 is pressed bya visitor. When pressed, the button 2133 may trigger one or morefunctions of the device 2130, as further described below.

The motion sensor 2132 may be, for example, one or more passive infrared(PIR) sensors that detect motion using the infrared wavelength, but maybe any type of sensor configured for detecting and communicating thepresence of motion and/or a heat source within their field of view. Themotion sensor 2132 may be configured to detect motion using anymethodology, including but not limited to methodologies that do not relyon detecting the presence of a heat source within a field of view,without departing from the scope of the present embodiments. In certainembodiments, the infrared-transparent lens 2132A may be a Fresnel lenspatterned to focus incoming light onto the at least one motion sensor2132 located within the device 2130. The infrared transparent lens 2132Amay be substantially coplanar with a front surface of the housing 2131.In alternative embodiments, the infrared-transparent lens 2132A may berecessed within the housing 2131 or may protrude outward from thehousing 2131. The infrared-transparent lens 2132A may extend and curlpartially around the side of the device 2130 without departing from thescope of the present embodiments. The at least one motion sensor 2132 isconfigured to sense a presence and/or motion of an object in front ofthe device 2130. In certain embodiments, the optically-transparent lens2134A may be configured for focusing light into the camera 2134 so thatclear images may be taken. The camera 2134 is configured for capturingvideo data when activated.

Changes may be made in the above methods, devices, and systems withoutdeparting from the scope of the present embodiments. It should thus benoted that the matter contained in the above description and shown inthe accompanying drawings should be interpreted as illustrative and notin a limiting sense. The following claims are intended to cover genericand specific features described herein, as well as all statements of thescope of the present method and system, which, as a matter of language,might be said to fall therebetween.

What is claimed is:
 1. A doorbell switch, comprising: an input device;and a transmitter operably connected to the input device such that, whenthe input device receives an input to activate a doorbell sound outputdevice, the transmitter generates an activation signal on wiringelectrically coupling the doorbell switch to a doorbell sound outputdevice controller, the activation signal being selected from the groupconsisting of a simple tone and a modulated tone.
 2. The doorbell switchof claim 1, further comprising power supply circuitry that receivesinput electrical power via the wiring electrically coupling the doorbellswitch to the doorbell sound output device controller, to electricallypower the doorbell switch.
 3. The doorbell switch of claim 2, furthercomprising activation circuitry including the transmitter, wherein theactivation circuitry and the power supply circuitry are electricallycoupled in parallel with the wiring electrically coupling the doorbellswitch to the doorbell sound output device controller.
 4. The doorbellswitch of claim 1, wherein the transmitter generates the activationsignal such that the activation signal is a differential signal on thewiring electrically coupling the doorbell switch to the doorbell soundoutput device controller.
 5. The doorbell switch of claim 1, wherein theinput device comprises a touch-activated switch.
 6. The doorbell switchof claim 1, further comprising a video camera that generates video imagedata representing a scene proximate to the doorbell switch.
 7. Thedoorbell switch of claim 1, further comprising a microphone thatgenerates sound data representing sound proximate to the doorbellswitch.
 8. A doorbell switch, comprising: an input device; andperturbation circuitry including a perturbation switching device and animpedance device electrically coupled in series, the perturbationcircuitry operably connected to the input device such that, when theinput device receives an input to activate a doorbell sound outputdevice, the perturbation circuitry generates an activation signal onwiring electrically coupling the doorbell switch to a doorbell soundoutput device controller by changing electrical current flowing throughthe wiring.
 9. The doorbell switch of claim 8, further comprising powersupply circuitry that receives input electrical power via the wiringelectrically coupling the doorbell switch to the doorbell sound outputdevice controller, to electrically power the doorbell switch.
 10. Thedoorbell switch of claim 9, further comprising activation circuitryincluding the perturbation circuitry, wherein the activation circuitryand the power supply circuitry are electrically coupled in parallel withthe wiring electrically coupling the doorbell switch to the doorbellsound output device controller.
 11. The doorbell switch of claim 8,wherein the impedance device comprises one or more resistors.
 12. Thedoorbell switch of claim 8, wherein the input device comprises atouch-activated switch.
 13. The doorbell switch of claim 8, furthercomprising a video camera that generates video image data representing ascene proximate to the doorbell switch.
 14. The doorbell switch of claim8, further comprising a microphone that generates sound datarepresenting sound proximate to the doorbell switch.
 15. A method foroperating a doorbell sound output device, the method comprising:receiving a command input at a doorbell switch; in response to receivingthe command input, generating a tone on wiring electrically coupling thedoorbell switch to a doorbell sound output device controller external tothe doorbell switch, the tone being selected from the group consistingof a simple tone and a modulated tone; receiving the tone at thedoorbell sound output device controller; and in response to receivingthe tone at the doorbell sound output device controller, enabling flowof electrical current between the doorbell sound output devicecontroller and the doorbell sound output device.
 16. The method of claim15, further comprising generating the tone in a differential manner onthe wiring electrically coupling the doorbell switch to the doorbellsound output device controller.
 17. The method of claim 15, furthercomprising electrically powering the doorbell switch from power supplycircuitry electrically coupled to the wiring electrically coupling thedoorbell switch to the doorbell sound output device controller, whilegenerating the tone.
 18. The method of claim 15, further comprisingdetecting, at the doorbell sound output device controller, a signalhaving a frequency of the tone.
 19. The method of claim 15, furthercomprising filtering the tone from other signals received at thedoorbell sound output device controller.
 20. The method of claim 15,further comprising: operating a switching device in a conductive stateto enable flow of electrical current between the doorbell sound outputdevice controller and the doorbell sound output device; receiving, atthe doorbell sound output device controller, a configuration command;and adjusting, in response to the configuration command, a duration thatthe switching device operates in its conductive state.